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This paper aims to understand the outlet temperature distribution of the combustor of a high-temperature, high-speed heat-airflow simulation system.

The paper uses numerical simulation to study the temperature distribution of the combustor of a high-temperature, high-speed heat-airflow simulation system. First, the geometrical model of the combustor and the combustion model of the fuel are established. Then, the combustion of fuel in the combustor is simulated by using FLUENT under various conditions. Finally, the results are obtained.

The paper found three conclusions: when the actual fuel–gas ratio is equal to the theoretical fuel–gas ratio, the temperature in the combustor of the high-temperature, high-speed heat-airflow simulation system (HTSAS) can reach its highest and the distribution is the most uniform. Although increases in the total temperature of the inlet air can increase the highest temperature in the combustor of the HTSAS, the average temperature of the combustor outlet will decrease. At the same time, it will lead to an uneven temperature distribution of the combustor outlet. When the spray angle of the kerosene droplet is at 30 degrees, the outlet temperature field of the combustor is more uniform.

The paper presents a method to analyze the combustion performance of fuel and the gas temperature distribution in the combustor. The results will lay the foundation for the gas temperature control of a combustor.

This research aims to provide a theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and V-shaped substrate, which also gives guidance for those complicated welding operation objects in brazing technique.

Wetting experiments were performed to measure the contact angles at different temperatures of molten Sn-3.0Ag-0.5Cu wetting on the quartz substrate with an included angle of 90°. According to the experimental results, the theoretical spreading morphology of molten solder on V-shaped substrate at corresponding temperature was simulated by Surface Evolver.

The theoretical morphology profiles of the molten solder sitting on the V-shaped substrate are simulated using Surface Evolver when the molten solder reaches spreading equilibrium. The spreading mechanisms as well as the impact of surface tension and gravity on interfacial energy of the molten solder wetting on the V-shaped groove substrate are also discussed where theoretical results agree well with experiment results. The contact area between the gas and liquid phases shows a tendency of first increasing and later decreasing. Otherwise, the spreading distance and the height of the molten solder increases as the droplet volume increases as the included angle and the contact angle are given as constants, and both the interfacial energy and the gravitational energy increase as well. This research has a wide influence on predicting the outcomes in commercial impact and also gives guidance for those complicated welding operation objects in brazing technique.

It is of very important significance in both science and practice to investigate the differences between the flat surface and V-shaped surface. Some necessary parameters including intrinsic contact angle and surface tension need to be directly measured when the droplet spreads on the flat surface. The relevant simulation conclusions on the inherent characteristics can be given based on these intrinsic parameters. Compared with the flat surface, the V-shaped substrate is chosen for further discuss on the effects of gravity on the droplet spreading behavior and the changes of apparent contact angle which can only occurs as the substrate is inclined. Therefore, this research provides theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and substrate.

The research is developed for verifying the accuracy of the model built in Surface Evolver. Based on this verified model, other researches on the spreading distance along y-axis and the contact area that are especially difficult to be experimentally measured can be directly simulated by Surface Evolver, which can provides a convenient method to discuss the changes of horizontal spreading distance, droplet height and contact area with increasing the included angle of V-shaped substrate or with increasing the droplet volume. Actually, the modeling results are calculated for supplying the theoretical parameters and technical guidance in the welding process.

This research provides theoretical method and data supports for a future study on interfacial reaction mechanism and spreading mechanism between molten solder and substrate, which has a wide influence on prediction the outcomes in commercial impact and also gives guidance for those complicated welding operation objects in brazing technique.

Surface Evolver, can also be used to discuss the structure and spreading mechanism of droplets on V-shaped substrates, which have not been discussed before.

This study aims to develop a collaborative governance framework (CGF) to systematically investigate the impeding factors (IFs) in terms of the operational sustainability of PPPs. It examines the transmission pattern (i.e. the way in which network members react to each other) of the IFs network.

Literature review and interview were adopted to identify the IFs. Then, with the data collected from the interview in China, the social network analysis and interpretive structure model were synergised to examine the chain reaction, driving and dependent powers, and hierarchical structure of the identified IFs.

The results reveal that the cognition, institutional, financial and participation aspects are key barriers confronted by PPP sustainability, and the government plays a leading role in controlling factors causing sustainability-related problems in PPPs. Weak government leadership and institutional environment were identified as the most fundamental reasons triggering a chain of IFs, while project governance and management activities act as bridge nodes that play an intermediary role in the IFs network.

This research contributes to the literature on PPP governance by (1) bridging the literature gap through the development of CGF for explaining the governance of PPP sustainability with a holistic view that considers both macro environment and operational project processes; and (2) identifying the transmission pattern of IFs network which uncovers the underlying dynamics causing the unsustainable operation of PPPs.

This research provides practitioners with a list of key checkpoints for preventing failure escalation, enables decision-makers to prioritise obstacle-mitigation efforts and develop a feasible process to control PPP operation, and offers management countermeasures to remove the key barriers impeding PPP sustainability.

This study is novel for adopting network-oriented techniques to quantify the relative importance of the IFs and examine the transmission pattern of the IFs system. Therefore, it visualises the complex underlying dynamics causing unsustainable PPP operation, identifies root and direct causes of PPP failures, and provides decision-makers with insights into sustaining PPP sustainability from a network-oriented perspective.

This study investigated the differential effects of empowering leadership and directive leadership in projects. Moreover, how the complex interplay between empowering and directive leadership styles influences both leader–member exchange and project performance was also explored.

Polynomial regression analysis and response surface modeling were applied to analyze 161 matched data collected from project members and managers worked in different projects located in China.

Four leadership styles were identified, i.e. ambidextrous, delegating, directive and laissez-faire styles. These may be combined with empowering and directive leadership. With regard to (in)congruence, leader–member exchange and project performance improved with ambidextrous style as a form of high–high congruence between empowering and directive leadership compared with laissez-faire style (i.e. low–low congruence). Results were better when a delegating style was combined with empowering leadership at a high level compared with the combination of directive style as directive leadership at a high level. Leader–member exchange was identified to exert a mediating role of the (in)congruence on project performance.

This study confirmed the contingent viewpoint of leadership by identifying distinct leadership styles applied in projects. Furthermore, the co-existence of empowering leadership and directive leadership was examined, and the underlying mechanism between the (in)congruence of empowering and directive leadership and project performance was identified.

This study aims to investigate the influence mechanism of expatriates' cultural intelligence (CQ) on expatriate effectiveness (task performance and premature return intention), identifying work engagement as a mediator and cultural distance as a boundary condition.

Drawing on the conservation of resource theory and the person–environment fit (P–E fit) theory, a moderated mediation model is built. Working with a sample of 303 international construction expatriates collected by snowball sampling, the hypotheses are tested by using the structural equation model analysis.

Work engagement partially mediates the relationship between expatriates' CQ and task performance, as well as fully mediates the relationship between expatriates' CQ and premature return intention. Cultural distance moderates the positive relationship between CQ and work engagement, as well as moderates the mediating effects of work engagement.

The impacts of potential moderators (e.g. work–family conflict and organizational culture) on the relationship between CQ and expatriate effectiveness have not been considered in this study.

This study is useful for international construction firms to optimize the allocation of human resources.

This study contributes to the expatriate literature by adding empirical evidence to explain the influence mechanism of expatriates' CQ on expatriate effectiveness.

Measuring the performance of public participation is conducive to improving participation systems. However, such measurement, particularly in urban regeneration projects, is difficult because of the complex indicators and multiple stakeholders involved. The purpose of this paper is to measure the public participation level in urban regeneration projects in China.

This study adopts a perception difference-based method to measure the public participation level in urban regeneration projects in China. Specifically, an indicator system consisting of 12 indicators from three categories was first purposed. A perception difference-based method that integrates ANOVA test and Tukey test were then developed. The method was validated using five represented projects, and the results are interpreted based on a proposed measurement matrix.

Regardless of the type of indicator, the perception of the government aligns with the perception of private sector professions, however, deviates from the perception of citizens. By taking the mean score and the significance level among stakeholders of perception as two dimensions, different patterns of issues in the current participation practice in urban regeneration are manifested.

Theoretically, the proposed indicator system and perception difference-based method combined to provide a holistic view of public participation, which is verified to provide a better measurement. Practically, the authors’ methodology helps in revealing issues in current participation practice and further leading to designing coping strategies. Nonetheless, the proposed method requires further validation in participation practices in China and other countries.

By considering the perception mean and the significance level as two dimensions, a public participation measurement matrix is proposed. The performance in different indicators are classified into four stages accordingly, namely idling, starting, running-in and accelerating.

This study aims to develop a Stackelberg Game Model for seeking the optimal subsidy plans with varying levels of government financial capability (GFC). Furthermore, the scenario-based analysis is conducted and will enable governments to identify a comprehensive subsidy plan as follows: improve project performance and optimise social welfare.

A Stackelberg Game Model is developed to optimise the effectiveness of subsidies on the performance of public-private partnerships (PPPs).

According to the scenarios that are generated from the model, governments that are confronting with limited public budgets could reduce the intensity of performance incentives and increase the participation-oriented subsidy. Whilst a participation-oriented subsidy can stimulate private organisations’ willingness to participate in infrastructure PPPs, a performance-oriented subsidy is capable of facilitating the projects’ performances. Intuitively, the performance-oriented subsidy enables the private entities of PPPs to improve their efforts on the projects to realise higher profits. However, the participation-oriented subsidy is unable to affect the level of their effort spent on the projects. To satisfy both parties’ expectations in a PPP, the performance-oriented subsidy needs to be prioritised for a purpose of enabling higher quality outputs.

The game model developed in this study contributes to the literature by offering new insight into the underlying mechanism of governments and private entities, in terms of their decision-making for subsidy planning and contributions (i.e. resource allocation and spending) during the life-cycle of PPPs. This research enriches the government subsidy model by revealing the effects of the GFC and clarifies the impacts of two different schemes of subsidy on the performance of PPPs.

The government has been conventionally viewed as being omnipotent to provide PPPs with a wide range of subsidies. However, the subsidies are not unlimited, due to GFC. In addressing this void, this study has modelled the impacts of government subsidy plans with a consideration of GFC-related constraints. The combined effects of the participation- and performance-oriented subsidies on the project performance of PPPs have been examined.

The sustainable success of infrastructures is becoming a driving force for advancing urbanization globally. However, to achieve infrastructure sustainable success (ISS), how project management practices (PMPs) play their role remains unexplored in current literature. To this end, an empirical study on whether PMPs play significant impacts on the accomplishment of ISS was conducted.

This research is based on an empirical survey of domestic and overseas infrastructure projects managed by Chinese companies. 162 data samples were collected and further analyzed deploying structural equation modeling (SEM) on the basis of goal-setting theory. PMP factors derived from the plan-do-check-act (PDCA) ideology, i.e. culture, strategy, implementation and reflection were hypothesized and validated to have direct and indirect relationships with ISS.

The results of this study indicate that both culture and reflection can directly drive the PMPs toward ISS. Furthermore, it is revealed that by affecting mediator factors of strategy, implementation and reflection, culture is found to present an indirect influence on ISS; by affecting mediator factors of implementation and reflection, Strategy is found to present an indirect influence on ISS and by affecting the mediator factor of reflection, implementation is found to present an indirect influence on ISS.

These findings contribute to the body of knowledge in measuring sustainability success of project management performances by clarifying critical relationships of how PMPs lead to ISS. Prospectively, the outputs of this research will generate informative insights for practitioners to improve their PMPs in the process of pursuing ISS in future infrastructure management practices.

The performance of public–private partnerships (PPPs) can be determined by a variety of factors, i.e. influencing factors (IFs). This study is undertaken for a purpose of identifying how such factors determine the project's performance (i.e. factor transmission patterns), particularly from the key stakeholders' perspectives.

A hybrid approach, which comprises a Social Network Analysis, ISM (i.e. Interpretive Structural Modeling) and an improved DEMATEL (i.e. Decision-Making Trail and Evaluation Laboratory), was developed to analyze the causal relationships between the identified IFs as well as the transmission patterns of their impacts on PPPs. Data were collected from interviews and questionnaire surveys.

The transmission patterns of the identified IFs cascade from project environment and features and stakeholders' relationship to the project company capabilities and project process. It is identified that the public authority has a higher level than that of the private entity in PPPs.

It lacks longitudinal studies to investigate the dynamics of PPP stakeholder relationships and social networks. Future research needs to explore the transmission patterns of sub-factors affecting PPP performance and extend the applicability of the developed hybrid approach.

This research provides practitioners with a robust tool that is useful for and insights into enhancing the management of lifecycle performance. It ensures the public authorities and private entities embarking on PPPs will make an informed decision about the monitoring of the life cycle performance.

This study contributes to knowledge of managerial mechanisms that can be adopted to manage factors determining the performance of PPPs. It enables an understanding of stakeholders' roles in driving the life cycle performance of PPPs.

This study applied eye-tracking techniques and questionnaires within the framework of the Stimulus-Organism-Response Model (SOR) and Technology Acceptance Model (TAM), to investigate the influencing factors of the public acceptance of 5G base stations.

This study used a combination of eye-tracking experiments and questionnaires. The data were analyzed using partial least squares structural equation modeling (PLS-SEM).

(1) The Technology Acceptance Model (TAM) could be used to explain the effects on public acceptance of 5G base stations in the context of the COVID-19 pandemic. The public's perceived usefulness and ease of use of 5G base stations positively affects public acceptance of 5G base stations. (2) The public's perceived risk of 5G base stations has a negative influence on the public acceptance of 5G base stations. (3) The public's visual attention to the different valence information about 5G base stations positively impacts the perceived ease of use while having negative impacts on perceived risk. (4) Visual attention to various valence information of 5G base stations can indirectly influence public acceptance through the perceived risk.

Applying the SOR and TAM to data obtained from eye-tracking experiments and questionnaires, this study analyzed the factors and mechanisms influencing public acceptance of 5G base stations in the context of the COVID-19 pandemic.